Among the maintenance situations in a telecommunication system that are difficult to resolve is the condition of chronic dropped or cut-off calls at a customer's location. The difficulty arises from a limited ability to readily isolate the cause of the dropped calls as either the telecommunication network or customer premises equipment (CPE).
Some of the events which often take place during the process of analyzing and rectifying a chronic dropped call problem are described below. While the events described below may not all be inflicted upon any one customer, they are typical of the difficulties that may arise. Typically, a customer reports the problem of dropped calls to a service assistance center.
Upon a customer's first report, the service assistance center may avoid dispatching a technician until remotely-administered diagnostic tests have been completed without finding the fault. If a technician must be dispatched, there may be little he can do unless a dropped call actually takes place during his presence. If no dropped call occurs, the customer may insist that the technician attempt some repair action without assurance that the fault is being corrected. Sophisticated monitoring equipment can be used to record all events for later analysis, but technicians typically do not have ready access to this equipment or the skill to use it.
If the technician's action does not resolve the problem, a field engineer may be dispatched with chart recording equipment to monitor signals on suspicious central office telecommunication lines or trunks. Devices which gather voltage data from multiple channels are known in the art. These devices record all monitored electrical signals for later analysis. Some of these devices also store and display the data on a personal computer screen. Such equipment can be used by a field engineer to monitor signals on telecommunication lines and trunks. Much of the field engineer's time, however, may be spent waiting for an instance of a dropped call to occur. Additionally, the customer may be billed by either the local telephone company or the customer equipment service provider if no problem is found in the respective system.
The events described above, among others, suggest the need for a device which quickly and positively isolates the cause of dropped calls to either the telephone network or customer premises equipment (CPE).